Effect of Cycloxydim Herbicide for Control of Grassy Weeds in Onion

Abstract

A field experiment was carried out during rabi (winter) season of 2013-14 to evaluate the effect of new herbicide cycloxydim 20% emulsifiable concentrate (EC) against grassy weeds and its phytotoxic effect on onion crop as well as on the succeeding crop. The results showed that herbicide treatments increased marketable yield significantly compared to weedy check and hand weeded plot. Post-emergence application of cycloxydim 20% EC (@ 100 g a.i.-1) and methylated seed oil (MSO) adjuvant at three-to-four leaf stage showed marketable yield at par with quizalofop-ethyl 5% EC, fenoxaprop ethyl 9% EC and propaquizalofop 10% EC. All the herbicide treatments produced significantly higher marketable bulb yield compared to weedy check and hand weeded plot and also exhibited 100 % weed control efficiency (WCE) against grassy weeds viz., Brachiaria mutica, Setaria verticillata, Cyperus rotundus and Cynodon dactylon. The post-emergence application of cycloxydim 20% EC + MSO adjuvant produced 80.3% higher marketable yield than weedy check. Herbicides evaluated under the present experiment had no phytotoxic effect on onion crop and residual effect on its succeeding nursery. This indicates that cycloxydim 20% EC + MSO adjuvant provides a better option in addition to existing herbicides to manage monocot weeds in onion agro-ecosystem.